1. Field of the Invention
The present invention relates to a post-cure inflator for performing expansion cooling to a vulcanized tire, a rim exchange method thereof and a rim.
2. Description of the Related Art
Conventionally, in a post-cure inflator, in a state that the air is enclosed into a vulcanized tire and a shape is properly retained, the tire is cooled to a temperature at which contraction of a reinforcement fiber is settled such as 100 degrees or less or 80 degrees or less.
Japanese Patent Laid-Open No. Sho51-61582 discloses a post inflator device of two cycles having upper and lower rims on the upper side and the lower side of a laterally installed center frame respectively, in which a tire released from a vulcanizer is sandwiched by the upper and lower rims positioned on the lower side of the center frame so as to perform expansion cooling, at the time, the upper and lower rims already positioned on the lower side of the center frame are positioned on the upper side of the center frame by 180 degree rotation of the center frame so as to continue the expansion cooling, and the upper and lower rims positioned on the upper side of the center frame so as to perform the expansion cooling of the tire are positioned on the lower side of the center frame so as to release the tire to which the expansion cooling is completed and receive a new tire. Then, the upper and lower rims are exchanged in accordance with a bead diameter or bead width of the tire to which the expansion cooling is performed.
Japanese Patent No. 2799256 discloses a post-cure inflator for performing expansion cooling of a tire at two cycles as well, in which a lower rim is sidable in the direction orthogonal to the axial direction, the lower rim slid to a position apart from a center axis of upper and lower rims receives the tire released from a vulcanizer and returns to a position corresponding to the center axis of the upper and lower rims, then the lower rim is brought closer to the upper rim in the axial direction, and the tire is sandwiched by the upper and lower rims and the expansion cooling is performed so that centering to the lower rim of the tire can be surely performed and an increase in size can also be prevented, and a conveyance device thereto. Since the lower rim is a sliding type, the upper and lower rims are easily exchanged.
Japanese Patent Laid-Open No. Hei5-131463 discloses post-cure inflator upper and lower rims for performing expansion cooling of a tire at two cycles as well capable of sandwiching tires in various sizes without exchanging an upper rim by providing differences in a steps shape having at least two outer diameters or more in the upper rim, and an upper and lower rim exchange device.
In tires on the market in recent years, bead diameters approximately from 12 inches to 24 inches are adopted in accordance with a type of an automobile to which the tires are installed. Even when the bead diameter is the same, a plurality of bead width are standardized. Therefore, in Japanese Patent Laid-Open No. Sho51-61582 and Japanese Patent No. 2799256, there is a need for selecting and exchanging rims for every type of the tires to which the expansion cooling is performed and further adjusting a rim clearance.
At this point, in Japanese Patent Laid-Open No. Hei5-131463, the tire of various bead diameters can be sandwiched without exchanging the rims. However, when the number of steps is increased so as to add a bead diameter to be treated, width of the step is narrowed and bead portions of the tires cannot be surely sealed. When the number of steps is increased so as to add the bead diameter to be treated, thickness of the rims is increased and a pair of the rims is not easily sufficiently brought closer to each other. That is, the tire with a larger bead diameter and narrower bead width is not easily sandwiched by a pair of the rims.